吸光光度法测定内燃机车冷却液中亚硝酸根含量

ABSORPTIOPHOTOMETRIC DETERMINATION OF NITRITES IN COOLING LIQUOR FOR DIESEL LOCOMOTIVE

研究了藏红T与亚硝酸根在硫酸介质中的显色反应,反应产物在近紫外区有一灵敏的吸收峰,其λ_(?)为350nm,据此建立了一个简单、快速、选择性好的测定NO_2^-的新方法.NO_2^-浓度在0～1.8μg·ml^(-1)内服从比耳定律,用于内燃机车冷却液中NO_2^-的测定,结果与盐酸萘基乙二胺比色法一致.

A new selective and simple spectrophotometric method for the determination of nintrites in cooling liquor for diesel locomotive is proposed in this paper. Nitrite reacts with safranine T in acidic medium (H2SO4) to form a product which is measured at 350nm. Beer's law is obeyed over the concentration of nitrite of 0 -1. 8μg ·ml-1. The proposed method has been applied to the determination of nitrites in cooling liquor for diesel locomotive. The results obtained are quite satisfactory and are in agreement with those obtained by the N-(l-naph-thgl) ethylenediamine dihydrochloride photometric method.